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We report on proton radiation effects on Si-nanocrystal (Si-NCs) MOS capacitors and nMOS transistors aiming at non-volatile memory applications. Irradiation experiments were conducted on NC MOS capacitors using protons of 1.5 MeV and 6.5 MeV and on NC nMOS transistors using protons of 1.5 MeV. The range of doses investigated was ~ 1 to ~ 100 Mrad(Si[O.sub.2]). A 2-D layer of Si NCs with ~ 3 nm mean diameter and [10.sup.12] [cm.sup.-2] surface density was successfully achieved by low-energy (1 keV) ion-beam-synthesis in thin Si[O.sub.2] layers. After irradiation, programmed capacitors are found to undergo bit flip while programmed transistors are not. Charge retention measurements at room temperature for the write and erase states of irradiated and non-irradiated samples reveal that a significant memory window exists at an extrapolated time of ten years even after an irradiation dose as high as 120 Mrad (Si[O.sub.2]). The flat-band decay rate of the erase state in NC MOS capacitors does not depend on the irradiation-dose while the opposite occurs for the write state which is found to be directly dependent on [D.sub.it] values after irradiation. These results clearly indicate that NC Non-Volatile Memories (NVM) are promising radiation tolerant devices. Index Terms--Data retention, nanocrystal memories, nonvolatile memory (NVM), proton radiation effects. more...

Isotopically pure material was used in diffusivity measurements of silicon in silicon dioxide layers.

A new study uses the wafer bonding technique to investigate the interaction between silicon interstitials and dislocation loops during thermal oxidation.

The interstitial injection during nitrous oxidation of silicon at low temperatures was monitored using dislocation loops and boron-doped delta layers.

A model for the time dependence of the surface recombination velocity of silicon interstitials at nonoxidizing or inert Si/SiO2 interfaces was developed. The model considers the experimentally observed diffusion of silicon interstitials through a thermal oxide. It was observed that the model can accurately simulate one-dimensional and two-dimensional experiments. The segregation coefficient of silicon interstitials at the silicon-oxide interface can be obtained from experimental data. more...

Research was conducted to collate growthand shrinkage of oxidation stacking faults (OSF) in silicon implanted with oxygen (SIMOX) and bulk silicon. SIMOX exhibited lengthier faults which may be attributed to silicon interstitial supersaturation. Results revealed that OSF shrinkage in N2 was the same for SIMOX and bulk silicon samples. Data also provided clearer insights on the basic properties of siicon self-interstitials. more...

Si overlayer in silicon separated by oxygen oxidation results in oxidation stacking faults (OSF) due to Si interstitials generation. Low OSF densities result due to migration of Si interstitials to the bulk silicon. This movement can be suppressed when a high density of microdefects are produced in the Si layer. The size distribution of OSF shows that the nucleation regime is neithertotally homogenous nor totally heterogenous. more...

Several arsenic and phosphorus diffusion experiments are conducted to explain the diffusion, as well as the activation phenomenon taking place in the codoped germanium substrates. The results demonstrate the presence of extremely low activation levels for the codoped samples. more...

Phosphorus diffusion and activation related phenomena in germanium is described and both conventional thermal processing and laser annealing is used by pulsed nanosecond Nd:YAG laser. A combined laser thermal treatment above the melting threshold prior to conventional annealing has allowed the elimination of the implantation damage in order to understand the impact of defects on both transient dopant diffusion and outdiffusion. more...

Electrical properties of ultra thin gate oxides formed by oxidation of nitrogen implanted silicon and nitrogen distribution were studied. Absence of extended defects in the silicon substrate and lower interfacial damaged have resulted in better nitrogen distribution in the 3 and 25 KeV implanted samples which were identical. more...

A nonvolatile electrically erasable programmable read-only memory device using gold nanoparticles as charge storage elements deposited at room temperature by chemical processing is demonstrated. The device exhibits significant threshold voltage shifts after application of low-voltage pulses (less than or equal to plus-minus 6 V) to the gate and has nonvolatile retention time characteristics. more...

The measured Si diffusivity in thermal SiO2 with an experimental method based on isotopic exchange in equilibrium conditions are discussed. The resulting values are compared with literature data and the possible origin of the observed difference is described. more...

The influence of the implantation energy on oxidation kinetics in nitrogen-implanted silicon was investigated. Ultrathin oxides in the range of present industrial interest can be achieved without creating extended defects in the channel region by using low energy-high dose nitrogen implantation. more...